         measurement (generate-measurement-f unit)]
     [measurement (measurement-as-f measurement (first (remove (partial = unit) units)))]))
 
-(generate-pair #{:psi :kPa} rand-pressure-unit typical-surface-treating-pressure pressure-as)
+(generate-pair #{:lbf :N} rand-force-unit typical-force force-as)

                   [:kg-per-m3 :lb-per-cu-ft] #(/ % (factors [:lb-per-cu-ft :kg-per-m3]))
                   [:ft-lb :J]                #(* % (factors [:ft-lb :J]))
                   [:J :ft-lb]                #(/ % (factors [:ft-lb :J]))
                   [:lbf :N]                  #(* % (factors [:lbf :N]))
                   [:N :lbf]                  #(/ % (factors [:lbf :N]))
                   [:ft :m]                   #(/ % (factors [:m :ft]))
                   [:m :ft]                   #(* % (factors [:m :ft]))
                   [:kg :lb]                  #(* % (factors [:kg :lb]))

         typical-pressure-psi                 (magnitude (typical-surface-treating-pressure :psi))
         typical-force-lbf                    (* typical-pressure-psi typical-casing-area-sq-inches)]
     (condp = force-unit
       :lbf (make-measurement typical-force-lbf force-unit)
       :N   (force-as (typical-force :lbf) :N)))))

(defn typical-power
  ([] (typical-power (rand-power-unit)))
